# Magnite Exchange API (xAPI) OpenRTB Extensions

**Canonical:** https://apis.io/apis/magnite/rubicon-project-openrtb-xapi/  
**Provider:** Magnite — https://apis.io/providers/magnite/  
**Base URL:** https://github.com/MagniteEngineering/xapi-proto  
**Documentation:** https://github.com/MagniteEngineering/xapi-proto

Magnite Exchange API (xAPI) OpenRTB Extensions is one of 78 APIs that [Magnite](https://apis.io/providers/magnite/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include OpenRTB, Real-Time Bidding, and Protobuf.

Magnite's Exchange API (xAPI) protobuf extensions to the IAB OpenRTB 2.x protobuf definitions, published in the open on GitHub. Defines Magnite-specific OpenRTB extension fields (extension IDs in the 5100-5299 range) for the AdEngine bidding endpoint, including window/iframe geometry, key-value pairs and supply-chain signals used by demand partners bidding into the Magnite exchange.

## Machine-readable artifacts (2)

- **Protobuf** — https://raw.githubusercontent.com/api-evangelist/magnite/refs/heads/main/grpc/rubicon-project-openrtb-xapi.proto
- **SourceCode** — https://github.com/MagniteEngineering/xapi-proto

## Other Magnite APIs (12)

- [Magnite Account Partner Segments API](https://apis.io/apis/magnite/magnite-account-partner-segments-api/)
- [Magnite Accounts API](https://apis.io/apis/magnite/magnite-accounts-api/)
- [Magnite Advertiser Domain Lists API](https://apis.io/apis/magnite/magnite-advertiser-domain-lists-api/)
- [Magnite App Bundle Lists API](https://apis.io/apis/magnite/magnite-app-bundle-lists-api/)
- [Magnite App Name Lists API](https://apis.io/apis/magnite/magnite-app-name-lists-api/)
- [Magnite Audiences API](https://apis.io/apis/magnite/magnite-audiences-api/)
- [Magnite Audios API](https://apis.io/apis/magnite/magnite-audios-api/)
- [Magnite Auth API](https://apis.io/apis/magnite/magnite-auth-api/)
- [Magnite Bid Maps API](https://apis.io/apis/magnite/magnite-bid-maps-api/)
- [Magnite Bills API](https://apis.io/apis/magnite/magnite-bills-api/)
- [Magnite Campaigns API](https://apis.io/apis/magnite/magnite-campaigns-api/)
- [Magnite Changelogs API](https://apis.io/apis/magnite/magnite-changelogs-api/)

## Tags

OpenRTB, Real-Time Bidding, Protobuf

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/magnite/rubicon-project-openrtb-xapi/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/magnite/.